AB0469 BASELINE MODIFIED TOTAL SHARP SCORE MAY BE A PREDICTOR FOR FLARE AND SUCCESSIVE JOINT DAMAGE IN TAPERING OF METHOTREXATE
Authors: K. Tanaka, K. Yujiro, T. Kawahata, M. Yuichi, T. Okubo, T. Sato, S. Abe, H. Ito, K. Katayama
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Many studies have reported the reduction or discontinuation of biologics in the treatment of rheumatoid arthritis (RA). In contrast, studies on tapering methotrexate (MTX) have been limited [1,2]. We prospectively reported whether bone destruction will progress at 48 weeks after tapering or discontinuing MTX in 79 RA patients in this meeting[3]. 34 patients (total 113 patients) were added for further analysis. <h3>Objectives</h3> According to tapering response, predictors for successful tapering MTX and progression of bone destruction were determined. <h3>Methods</h3> The subjects were RA patients who had maintained low disease activity or lower for 24 weeks or more in DAS28-CRP after MTX administration. Patients having PDUS Grade 2 or 3 per site by bilateral hand ultrasonography (26 areas) were excluded in this study owing to risk for joint destruction. Tapering of MTX dose was done every 2-3 months based on "shared decision between the patient and doctor.'' The joint destruction was evaluated by joint X-ray evaluation by modified total Sharp scoring (mTSS) at 1 year after the start of tapering MTX. Evaluation of clinical disease activity, severe adverse events, and the continuation rate during MTX tapering were also evaluated. According to tapering response, predictors for successful tapering MTX and progression of bone destruction were determined. Statistical analysis was performed by t-test, Mann-Whitney U test or one-way analysis of variance using EZR ver 1.37[4]. <h3>Results</h3> Patients' demographic data were as follows, mean age:60.8 yrs, female: male: 88 pts:25pts, disease duration: 66.1 months, mean MTX dose: 8.51mg/week, mean DAS28-CRP: 1.55, ACPA:179.9 U/ml, ACPA positive(%): 72.6, RF: 48.1 IU/ml, RF(%):48.1, mean mTSS:17.6, ΔmTSS&gt;1: 8.8% (10 cases) According to previous report, 113 RA patients were divided into three groups; Flared (F) group (22 patients), Less tapering (L) group, (37 patients) Good tapering (G) group (54 patients). As shown in Table 1A, significant differences were observed among the three groups in MTX dose at 6M(F vs G, P&lt;0.01, L vs G, P&lt;0.01), MTX dose at 12M(F vs L, P=0.01. F vs G, P&lt;0.01, L vs G &lt;0.01), DAS28-CRP at 12M (F vs L,G,P&lt;0.05), ΔmTSS/y(Fvs G, P&lt;0.05), baseline CDAI value (L vs G group, P&lt;0.05), CDAI, SDAI at 12M(F vs G, P&lt;0.05, F vs L, P&lt;0.05), D-VAS at 12M(F vs L,G, P&lt;0.01). Table 1B shows significant differences between F group and unflared (L+G) group in baseline mTSS (P&lt;0.05), ΔmTSS/y(P&lt;0.01), CDAI,SDAI, doctor VAS at 12M(P&lt;0.01), MMP3 at 12M(P&lt;0.05). Severe adverse events; cancer(stomach, lung) 2, MTX associated lymphoma(brain) 1, pneumoniae 1. These results indicated baseline mTSS may be a predictor for flare and flare response may be a predictor for joint destruction. Baseline CDAI may be a predictor for good response. <h3>Conclusion</h3> Baseline mTSS may be a predictor for flare successive joint damage in MTX tapering. Keeping low CDAI not DAS28 is important for good tapering. <h3>References</h3> [1] Baker KF et al. J. Autoimmunity. 2019;105:102298. [2] Lillegraven S et al. ACR meeting. 2019; Abstract L08. [3] Katayama K et al. Eular meeting 2020;FRI 0127 [4] Kanda Y et al. Bone Marrow Transplant.2013;48:452-8. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.